Surface treating device

ABSTRACT

A surface treating device comprising a swivel bearing mechanism, an oscillating tube connected to the swivel bearing mechanism so as to be free to pivot about the axis center of the swivel bearing mechanism and such that with respect to the axis center, an end portion thereof is positioned on the side facing the object surface and the other end portion thereof is positioned on the side opposite to the object surface, a nozzle connected to the one end portion side of the oscillating tube, and a self-revolving/else-revolving mechanism connected to the other end portion side of the oscillating tube and making the nozzle self-revolve and else-revolve about the axis center of the swivel bearing mechanism. The self-revolving/else-revolving mechanism has a main crank rotatably positioned on an axis passing through the axis center of the swivel bearing mechanism, a subordinate crank having a rotating shaft mounted at a site eccentric from the axis of the main crank and having an axis obliquely intersecting the axis of the main crank, and a universal joint means connecting that site in the subordinate crank which is eccentric from the axis, to the other end portion side of the oscillating tube. A main bevel gear is disposed on an axis common to the main crank, and in the subordinate crank there is provided a subordinate bevel gear rotating integrally therewith and engaged with the main bevel gear.

TECHNICAL FIELD

This invention relates to a surface treating device capable of removingforeign matter, such as an old coating or rust, stuck onto the surfaceof an object, or of roughening the surface of an object, by ejecting ahigh pressure fluid such as water, or a high pressure fluid mixed withabrasive grains, toward the surface of the object.

The present invention also relates to a surface treating device capableof removing foreign matter, such as an old coating or rust, stuck ontothe surface of an object, or of roughening the surface of an object, byejecting a high pressure fluid such as water, or a high pressure fluidmixed with abrasive grains, toward the surface of the object, whilesuction-adhering to the surface of the object by the pressure of anambient fluid such as air or water and moving along the surface.

BACKGROUND ART

So far, ultrahigh pressure water jet equipment and sand blastingequipment have been put to practical use as surface treating deviceswhich eject a high pressure fluid such as water, or a high pressurefluid mixed with abrasive grains, toward the surface of an object, suchas an oil reservoir tank or a ship hull, thereby removing foreignmatter, such as an old coating or rust, stuck onto the surface of theobject; or roughening the surface of the object with the abrasive grainsejected, to make the surface prepared for coating; or cleaning thesurface of the object to carry out non-destructive testing.

The devices disclosed in the specification and drawings of U.S. Pat.Nos. 4,095,378 and 4,934,475 are typical examples of a surface treatingdevice which ejects a high pressure fluid such as water, or a highpressure fluid mixed with abrasive grains, toward the surface of anobject while suction-adhering to the surface of the object by thepressure of an ambient fluid such as air or water and moving along thesurface, thereby removing foreign matter, such as an old coating orrust, stuck onto the surface of the object; or roughening the surface ofthe object with the abrasive grains ejected, to make the surfaceprepared for coating; or cleaning the surface of the object to carry outnon-destructive testing.

Such a device capable of suction-adhering to the surface of an objectand moving along it has a case, a surface sealing means mounted on thecase and defining a pressure reduction space in cooperation with thecase and the surface, and a pressure reducing means for discharging afluid from the pressure reduction space to decrease the pressure insidethe pressure reduction space. The device can be moved by wheels asmoving means, other suitable element such as an endless track, or othersuitable moving means such as a vibration generating means. Uponactuation of the pressure reducing means, fluid inside the pressurereduction space is discharged to the outside. Owing to the difference influid pressure between the inside and outside of the pressure reductionspace, the fluid pressure acts on the case, and is then transmitted tothe surface of an object via the wheels or other receiver member. Underthis fluid pressure, the device is caused to suction-adhere to thesurface of the object. By driving the moving means in this state ofsuction-adhesion, the device moves along the surface of the object. Onthis device is mounted working unit such as a surface treating materialejecting means for ejecting a surface treating material, such as highpressure water or abrasive grains, toward the surface of the object. Inthe present specification, the surface treating material refers to amaterial, such as a high pressure fluid including high pressure water orcompressed air, abrasive grains, or the high pressure fluid mixed withabrasive grains, which can treat the surface of an object when ejectedfrom a nozzle to the surface.

In conventional ultrahigh pressure water jet equipment, about 20liters/minute of water pressurized to an ultrahigh pressure of about2,000 to 2,500 kilograms/cm² is ejected from a nozzle with a diameter of0.1 to 0.5 mm. Furthermore, this nozzle is revolved at a high speed ofabout 1,000 rpm with a diameter of gyration of about 400 mm on a planeparallel to the surface of an object 20 to 30 mm apart from the surface.During revolution, the nozzle is gradually moved along the surface ofthe object at a rate of about 3 meters/minute. Thus, the surface of theobject is treated continuously. The reason why the nozzle is revolved ata high speed is that the diameter of the nozzle is so small that itswidth of treatment is also small. If the nozzle is revolved at a lowspeed, the problem arises that the surface after treatment has beentreated in a linear form resulting only from a trail of the center ofthe moving nozzle, and not in a surface form. The connection between anultrahigh pressure hose for supplying the nozzle with ultrahigh pressurewater and the nozzle is by a swivel joint. That is, the use of a swiveljoint has thus far been absolutely necessary to supply ultrahighpressure water to the nozzle revolved at a high speed. This type ofjoint becomes out of order relatively frequently. This use of a swiveljoint is likely to make the performance of the ultrahigh pressure waterjet equipment unstable.

A possible method of mixing abrasive grains into a stream of ultrahighpressure water to be ejected from the nozzle is to mix abrasive grainsinto an ultrahigh pressure water stream on the upstream side of thenozzle. However, the nozzle for feeding the ultrahigh pressure water inthe ultrahigh pressure water jet equipment has a small diameter, thusmaking it difficult to mix abrasive grains, larger in diameter than thenozzle, into an ultrahigh pressure water stream on the upstream side ofthe nozzle. The mixing of abrasive grains into an ultrahigh pressurewater stream therefore requires that a mixing nozzle for mixingultrahigh pressure water with abrasive grains be provided downstream ofthe nozzle. Such a method is already in practical use with ultrahighpressure water jet equipment of a type in which the nozzle is notrevolved (e.g. ultrahigh pressure water jet equipment applied tocutting).

In the aforementioned ultrahigh pressure water jet equipment, however,the nozzle is revolved at a high speed, thus requiring that a swiveljoint be used for connection between the nozzle and the ultrahighpressure hose for supplying ultrahigh pressure water to the nozzle. Inorder to mix abrasive grains into a stream of ultrahigh pressure water,therefore, ultrahigh pressure water and abrasive grains have to besupplied separately to the rotating nozzle through two hoses, i.e., ahose for ultrahigh pressure water and a hose for abrasive grains, andconsequently, a swivel joint for a two-phase flow is required. However,such a swivel joint is difficult to produce. Thus, the aforementionedultrahigh pressure water jet equipment poses difficulty in mixingabrasive grains into an ultrahigh pressure water stream to be ejectedfrom the nozzle revolved at a high speed. Its treating capacity hasclear limitations. Specifically, because of the difficulty in mixingabrasive grains into an ultrahigh pressure water stream ejected from thenozzle revolved at a high speed, it is easy to peel off a soft coating,but it is difficult to remove a hard rust. Nor can the ultrahighpressure water jet equipment form an anchor pattern, i.e. roughness, onthe surface of an object, because its formation absolutely requires thatabrasive grains be ejected toward the surface of the object and causedto impinge thereon.

In the sand blasting equipment which roughens the surface of an objectby directing a jet of abrasive grains at the surface of the object, theuse of a swivel joint is absolutely necessary to supply abrasive grainsto the nozzle revolved at a high speed. This use of a swivel joint islikely to make the performance of the equipment unstable.

Also in the surface treating device capable of suction-adhering to thesurface of an object by the pressure of an ambient fluid such as air orwater and moving along the surface, the use of the nozzle revolved at ahigh speed requires the use of a swivel joint as a means of feeding ahigh pressure water stream or abrasive grains to the nozzle. Owing tothis use of a swivel joint, the performance of the equipment may becomeunstable. For the same reasons as stated previously, moreover, it isdifficult to mix abrasive grains into a high pressure water streamejected from the nozzle revolving at a high speed. Thus, this devicealso faces the same problems as does the ultrahigh pressure water jetequipment.

DISCLOSURE OF THE INVENTION

Therefore, a principal object of the present invention is to provide asurface treating device which can feed a surface treating material to anozzle revolving at a high speed, without using a swivel joint, can thusmix abrasive grains into a high pressure fluid ejected from the nozzlerevolving at a high speed, and consequently has a further improvedtreating capacity.

Another object of the present invention is to provide a surface treatingdevice which can feed a surface treating material to a nozzle revolvingat a high speed, without using a swivel joint, thus has fewer troubles,and consequently has stable performance.

Still another object of the present invention is to provide a surfacetreating device which can revolve the nozzle, or make the nozzle revolveabout itself, and can feed a surface treating material to the nozzlerevolving at a high speed, without using a swivel joint, thus enabling amore homogeneous surface treatment which gives a treated surface havingless uneven quality.

A further object of the present invention is to provide a surfacetreating device which can feed a surface treating material to a nozzlerevolving at a high speed, without using a swivel joint, can thus givean improved treating capacity, and also prevent a substance to betreated--such as an old coating, rust or abrasive grains, which has beenpeeled off an object during surface treatment--from scattering to theoutside of the device to pollute the environment.

A still further object of the present invention is to provide a surfacetreating device which can feed a surface treating material to a nozzlerevolving at a high speed, without using a swivel joint, can thus mixabrasive grains into an ultrahigh pressure fluid ejected from the nozzlerevolving at a high speed, and consequently has a further improvedtreating capacity as well as stable performance, and can also enableefficient and remote-controlled safe surface treatment of the surface ofan object having a large surface area, such as an oil reservoir tank ora ship hull.

To attain the above-described principal object, the present inventionprovides a surface treating device having a nozzle for ejecting asurface treating material toward the surface of an object, whichcomprises

a swivel bearing mechanism, an oscillating tube connected to the swivelbearing mechanism so as to be free to pivot about the axis center of theswivel bearing mechanism and such that with respect to the axis center,an end portion thereof is positioned on the side facing the objectsurface and the other end portion thereof is positioned on the sideopposite to the object surface, the nozzle connected to the one endportion side of the oscillating tube, and aself-revolving/else-revolving mechanism connected to the other endportion side of the oscillating tube and making the nozzle self-revolveand else-revolve about the axis center of the swivel bearing mechanism,

the self-revolving/else-revolving mechanism including a main crank whichhas a driven shaft positioned on an axis passing through the axis centerof the swivel bearing mechanism on the other end portion side of theoscillating tube and rotationally driven by a driving means, and whichis rotationally driven integrally with the driven shaft; a subordinatecrank having a rotating shaft mounted at a site eccentric from the axisof the main crank and having an axis obliquely intersecting the axis ofthe main crank; a universal joint means connecting that site in thesubordinate crank which is eccentric from the axis, to the other endportion side of the oscillating tube; a subordinate bevel gear connectedto the rotating shaft of the subordinate crank and rotating integrallywith the subordinate crank; a main bevel gear which is providedintegrally on a shaft having an axis common to the driven shaft of themain crank and being disposed so as to be free to rotate relative to thedriven shaft, and which is engaged with the subordinate bevel gear; andthe subordinate bevel gear revolving about the main bevel gear accordingto the rotation of the main crank while revolving on its own axis.

In the self-revolving/else-revolving mechanism, when the main crank isrotationally driven by the driving means (e.g. a geared motor which isan electric motor), the subordinate bevel gear provided rotatably at asite eccentric from the axis of the main crank revolves about the mainbevel gear while revolving on its own axis. The rotating shaft of thesubordinate crank is connected integrally to the subordinate bevel gear,and the subordinate crank rotates integrally with the subordinate bevelgear. Thus, the revolution of the subordinate crank on its own axis, andthe revolution of the main crank about the other member are transmittedto the other end portion side of the oscillating tube (the end portionon the side opposite to the surface of the object) via the universaljoint means provided at a site eccentric from the axis of thesubordinate crank. On the other hand, the oscillating tube is free topivot about the axis center of the swivel bearing mechanism. Thus, thenozzle, which is connected to the one end portion side of theoscillating tube (the end portion on the object surface side) and ejectsthe surface treating material toward the surface of the object, iscaused to self-revolve and else-revolve about the axis center of theswivel bearing mechanism while revolving on its own axis. Such motionsof the nozzle result in a marked improvement in the surface treatingcapacity.

Of particular importance with the above-described actions is that theoscillating tube does not revolve on its own axis when the nozzle isself-revolving and else-revolving about the axis center of the swivelbearing mechanism at the same time, as stated above. As a result, thehose which supplies the surface treating material can be connected to aside surface (circumferential surface) on that other end portion side ofthe oscillating tube which is the end portion on the side opposite tothe surface of the object. Therefore, when the present invention is tobe applied to the surface treating device for ejecting only ultrahighpressure water from the nozzle, one hose for ultrahigh pressure water isconnected to the side surface on the other end portion side of theoscillating tube, and one flow path is provided within the oscillatingtube. One end of this flow path is connected to the ultrahigh pressurewater hose, and the other end thereof is connected to the nozzle,whereby the hose for ultrahigh pressure water and the nozzle can beconnected together via the oscillating tube as a joint. Since the hosefor ultrahigh pressure water and the nozzle are thus connected togethervia the oscillating tube as a coupling, no swivel joint is required.Consequently, there is obtained a surface treating device furtherimproved in treating capacity, relatively minimal in trouble, and thusstable in performance. Furthermore, the nozzle is capable of revolvingon its own axis as well as about other member, thus enabling an evenmore rapid surface treatment.

The aforementioned ultrahigh pressure water jet equipment had difficultyin mixing abrasive grains into an ultrahigh pressure water streamejected from a nozzle revolving at a high speed. Such mixing can beachieved without any problem when the present invention is applied toultrahigh pressure water jet equipment. That is, the device of thepresent invention makes it possible to connect a hose for supply ofabrasive grains as well as a hose for ultrahigh pressure water to theside surface on the other end portion side of the oscillating tube.Further, by providing two flow paths (a flow path for ultrahigh pressurewater and a flow path for supply of abrasive grains) within theoscillating tube, and connecting one end of the flow path for ultrahighpressure water to the hose for ultrahigh pressure water and the otherend of it to the nozzle, the hose for ultrahigh pressure water and thenozzle can be coupled together via the oscillating tube as a joint.Also, by connecting one end of the flow path for supply of abrasivegrains to the hose for supply of abrasive grains and the other end of itto a mixing chamber located downstream of the nozzle, the hose forsupply of abrasive grains and the mixing chamber located downstream ofthe nozzle can be coupled together via the oscillating tube as a joint.Namely, the hose for ultrahigh pressure water and the nozzle, and thehose for supply of abrasive grains and the mixing chamber locateddownstream of the nozzle, respectively, are coupled together via theoscillating tube as a joint, thus requiring no swivel joint. Hence, whenthe present invention is applied to ultrahigh pressure water jetequipment, not only peeling of a soft coating, but also removal of ahard rust can be performed easily. Formation of an anchor pattern on thesurface of an object can also be done readily.

The device of the present invention is also applicable to sand blastingequipment. Since the diameter of a nozzle for sand blasting is 8 to 14mm, a size much larger than abrasive grains, abrasive grains after beingmixed into compressed air can be ejected from the nozzle. Therefore, byconnecting one hose for supply of abrasive grains to the side surface onthe other end portion side of the oscillating tube, further providingone flow path for supply of abrasive grains within the oscillating tube,and connecting one end of this flow path to the hose for supply ofabrasive grains and the other end of it to the nozzle, the hose forsupply of abrasive grains and the nozzle can be coupled together via theoscillating tube as a joint. Since the hose for supply of abrasivegrains and the nozzle are so coupled together via the oscillating tubeas a joint, there is no need for a swivel joint.

In the device of the present invention, the main bevel gear can have itsshaft fixed so that this gear will not rotate. Preferably, however, inorder for the main bevel gear to rotate, if desired, in a directionopposite to the rotating direction of the main crank, its shaft isadapted to be rotationally driven by a driving means (an example is ageared motor, an electric motor) different from the driving means forthe main crank. By rotating the main bevel gear in a direction oppositeto the rotating direction of the main crank, the speed of revolution ofthe subordinate crank, i.e., the subordinate bevel gear, on its own axiscan be made even higher. As a result, the speed of revolution of thenozzle on its own axis can be made even higher, thus permitting an evenmore efficient surface treatment, and enabling a more homogeneoussurface treatment which gives a treated surface having less unevenquality.

One preferred embodiment of the swivel bearing mechanism according tothe present invention includes an annular main oscillating body having amain oscillating axis on a plane parallel to the surface of an object,and a plate-like subordinate oscillating body connected to the mainoscillating body so as to have a subordinate oscillating axisperpendicularly intersecting the main oscillating axis of the mainoscillating body, with the oscillating tube being connected to thesubordinate oscillating body. This construction gives the function thatthe respective shafts, on which the oscillating tube oscillates at highspeeds, can be maintained for long periods without wear, thus ensuringhigh durability and reliability. Moreover, the construction isrelatively simple, and can be produced at a relatively low cost.

In the device of the present invention, it is preferred that a space,which has as a boundary a plane parallel to the surface of an object andpassing the axis center of the swivel bearing mechanism, which ispresent between the boundary surface and the surface of the object, andwhich belongs to a zone where the oscillating tube and the nozzle move,is surrounded by a tubular case opening at both end portions, by thesurface, by a surface sealing means mounted at that one opening endportion of the case which faces the surface to seal a gap between thecase and the surface, and by an oscillating part sealing means forsealing a gap present between the other opening end portion in the casefacing the boundary surface and the oscillating tube, whereby a pressurereduction space is defined, the pressure reduction space being connectedto a pressure reducing means for discharging a fluid from the pressurereduction space to decrease the pressure inside the pressure reductionspace. When the pressure reducing means is actuated, a fluid in thepressure reduction space, such as the air, is expelled to the outside ofthe case, thereby reducing the pressure of the pressure reduction space.When the pressure reduction space is reduced in pressure, the device iscaused to suction-adhere to the surface of the object by the pressure ofan ambient fluid, such as the air, that acts due to the difference influid pressure between the inside and the outside of the pressurereduction space. The so constructed device makes it possible to feed asurface treating material to the nozzle rotating at a high speed,without using a swivel joint. Consequently, it becomes possible toimprove the surface treating capacity and prevent a substance to betreated--such as an old coating, rust or abrasive grains, which has beenreleased from the surface of the object during surface treatment--frombeing scattered to the outside of the device and polluting theenvironment. In this construction, the case is a stationary body, whilethe oscillating tube is a mobile body, so that the a gap (a sealablegap) is provided between the oscillating tube and the other opening endportion in the case facing the boundary surface. Since this gap issealed by the oscillating part sealing means, the pressure reductionspace can be formed easily.

Another preferred embodiment of the swivel bearing mechanism accordingto the present invention may be a known spherical bearing with a shaftholding hole (not shown). This spherical bearing is mounted on the otheropening end portion of the case. In the shaft holding hole is held theoscillating tube as passing through the hole. In the swivel bearingmechanism, a sealable gap is not provided between the oscillating tubeand the other opening end portion in the case facing the boundarysurface. However, the spherical bearing itself has a sealing function,and so there is no problem with the formation of the pressure reductionspace. When the spherical bearing is applied as the swivel bearingmechanism, a relatively highly reliable and relatively inexpensiveswivel bearing mechanism is obtained.

The device of the present invention is also preferably constructed suchthat the case is equipped with a moving means, the device is caused tosuction-adhere to the surface by the pressure of an ambient fluid actingon the case owing to the difference in fluid pressure between the insideand the outside of the case upon the actuation of the pressure reducingmeans, and the device is movable along the surface by the action of themoving means. When the pressure reducing means is actuated, a fluidwithin the pressure reduction space, such as the air, is expelled to theoutside of the case, thereby reducing the pressure in the pressurereduction space. When the pressure reduction space is reduced inpressure, the pressure of an ambient fluid, such as the air, which actson the case owing to the difference in fluid pressure between the insideand the outside of the pressure reduction space is transmitted to thesurface of the object via the moving means, resulting in thesuction-adhesion of the device to the surface of the object by thepressure of the ambient fluid. When the moving means is driven in thisstate of suction-adhesion, the device is moved along the surface of theobject as suction-adhered thereto. The so constructed device can feed asurface treating material to a nozzle revolving at a high speed, withoutusing a swivel joint, can thus mix abrasive grains into an ultrahighpressure fluid ejected from the nozzle revolving at a high speed, andconsequently has a further improved treating capacity as well as stableperformance, and can also enable efficient and remote-controlled safesurface treatment of the surface of an object having a large surfacearea, such as an oil reservoir tank or a ship hull.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a plan view showing an embodiment of a surface treating deviceconstructed in accordance with the present invention.

FIG. 2 is a view showing a part of the surface treating device of FIG. 1as a section taken on line 1--1, and the other part as a right sideview.

FIG. 3 is a sectional view taken on line 2--2 of the surface treatingdevice illustrated in FIG. 1.

FIG. 4 is a view showing a state in which the nozzle of the surfacetreating device illustrated in FIG. 2 is rotationally moved through 90°clockwise as viewed from the left end of FIG. 2, with a part of thedevice being shown as a section taken on line 1--1, and the other partas a right side view.

FIG. 5 is a partially enlarged view of the self-revolving/else-revolvingmechanism and the swivel bearing mechanism illustrated in FIG. 3.

FIG. 6 is a partially enlarged view of the self-revolving/else-revolvingmechanism illustrated in FIG. 5.

FIG. 7 is a partially enlarged view showing a state in which thesubordinate crank and the spherical joint of theself-revolving/else-revolving mechanism illustrated in FIG. 6 arerotationally moved through 180°.

FIG. 8 is a view of the surface treating device illustrated in FIG. 3,in which a part of the self-revolving/else-revolving mechanism isprovided with other embodiment.

FIG. 9 is a partially enlarged view of the self-revolving/else-revolvingmechanism illustrated in FIG. 8.

FIG. 10 is a sectional view conceptually showing the flow paths forultrahigh pressure water and abrasive grains in the oscillating tube andthe nozzle.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinbelow, a surface treating device improved in accordance with thepresent invention will be described in detail with reference to theappended drawings on the basis of embodiments of the surface treatingdevice capable of suction-adhering to the surface of an object andmoving along the surface.

With reference to FIGS. 1 to 3, a surface treating device shown entirelyat the numeral 2 has a case 4 which is hollow inside. In thisembodiment, the case 4 has a funnel-like portion 6 and a cylindricalportion 8 provided integrally as a continuation of the funnel-likeportion 6, and is tubular as a whole. An end portion of the cylindricalportion 8 defines one opening end portion of the case 4 facing thesurface, F, of an object, while the end portion of the funnel-likeportion 6 defines the other opening end portion of the case 4 facing theopposite side to the surface F. In this embodiment, the surface Fconsists of a flat surface. At the end portion of the cylindricalportion 8 is provided an annular plate 10 projecting radially outwardly.On the annular plate 10 is mounted a traveling portion seal 12constituting a surface sealing means which seals a gap between the case4 and the surface F. The traveling portion seal 12 is formed of arelatively flexible material such as urethane rubber or plastic. As willbe understood from FIGS. 2 and 3, the traveling portion seal 12 isnearly a torus in its entire form. The traveling portion seal 12 is incontact with the surface F, and defines a pressure reduction space 14 incooperation with the case 4, the surface F, and an oscillating partsealing means 88 to be described later. In the funnel-like portion 6 ofthe case 4 is formed an opening 16, to which a connecting pipe 18 isconnected. The connecting pipe 18 is connected to a pressure reducingmeans 22 via a flexible suction hose 20. The pressure reducing means 22may be composed of a suitable evacuating means such as a vacuum pump oran ejector. When the device 2 is to be used in a liquid such as water,the evacuating means may be composed of a drainage pump. Therefore, whenthe pressure reducing means 22 is actuated, a fluid inside the pressurereduction space 14, such as the air, is expelled to the outside via thesuction hose 20, whereupon the pressure reduction space 14 is reduced inpressure and the device 2 is caused to suction-adhere to the surface F.

At the outside of the case 4, i.e., the outside of the torus-likeportion 8 are fixed two case frames 24 located above the torus-likeportion 8 in FIG. 1, and case frames 26 located below the torus-likeportion 8 in FIG. 1. The case frame 24 has extensions 28 extending abovethe torus-like portion 8 parallel to each other at a distance in theright-and-left direction, and a mounting portion 30 extending betweenthese extensions 28, in FIG. 1. The respective case frames 26 compriseextensions 32 extending below the torus-like portion 8 parallel to eachother at a distance in the right-and-left direction in FIG. 1. To theupper surface, as viewed in FIG. 1, of the mounting portion 30 of thecase frame 24 is connected a transverse frame 34 by a connecting pin 36.To the end portion of each case frame 26 is secured a transverse frame38 by fastening bolts 40. A traveling frame 42 is fixed between one endof the transverse frame 34 (the right end in FIG. 1) and one end of thetransverse frame 38 (the right end in FIG. 1), while a traveling frame44 is fixed between the other end of the transverse frame 34 (the leftend in FIG. 1) and the other end of the transverse frame 38 (the leftend in FIG. 1). The traveling frames 34 and 38, and the traveling frames42 and 44 form a frame body substantially rectangular in the plan viewas shown in FIG. 1.

On the traveling frame 42 are mounted two wheels 46 constituting amoving means, a geared motor 48 constituting a rotary drive source, anda reduction gear mechanism 50. The respective wheels 46 are fixed toaxles supported rotatably on the traveling frame 42, and a sprocket 52is further fixed to each axle. The output shaft of the geared motor 48is connected to the input shaft of the reduction gear mechanism 50, anda sprocket 54 is fixed to the output shaft of the reduction gearmechanism 50. An endless roller chain 56 is wound over the sprockets 52and 54. When the geared motor 48 is energized (actuated), therefore,each wheel 46 is rotationally driven. Similar traveling equipment ismounted on the traveling frame 44, but its structure and actions aresubstantially the same as the aforementioned equipment mounted on thetraveling frame 42; hence, the same numerals will be assigned to thesame parts, and explanations omitted. If desired, instead of the wheels46, there may be employed another suitable moving element such as anendless track. Furthermore, the device 2 may be moved by other suitablemoving means such as a vibration generating means as disclosed in thespecification and drawings of U.S. Pat. No. 4,934,475.

With reference to FIGS. 1 to 5, the illustrated surface treating device2 includes a swivel bearing mechanism 60; an oscillating tube 62connected to the swivel bearing mechanism 60 so as to be free to pivotabout the axis center P1 of the swivel bearing mechanism 60 and suchthat with respect to the axis center P1, one end portion thereof ispositioned on the side facing the object surface F and the other endportion thereof is positioned on the side opposite to the surface F; anozzle 64 connected to the one end portion side of the oscillating tube62; and a self-revolving/else-revolving mechanism 100 connected to theother end portion side of the oscillating tube 62 to make the nozzle 64self-revolve and else-revolve about the axis center P1 of the swivelbearing mechanism 60.

The illustrated swivel bearing mechanism 60 includes an annular mainoscillating body 66 having a main oscillating axis L1 on a planeparallel to the surface F, and a plate-like subordinate oscillating body68 connected to the main oscillating body 66 so as to have a subordinateoscillating axis L2 perpendicularly intersecting the main oscillatingaxis L1 of the main oscillating body 66. The oscillating tube 62 isconnected to the subordinate oscillating body. More specifically, in themain oscillating body 66 comprising a circular ring-like plate member, arod end 74 is rotatably connected, at each of two sites on the mainoscillating axis L1, by a bolt 70, which is mounted so as to protruderadially inwardly of the main oscillating body 66, and a nut 72. Eachrod end 74 is fixed by a bolt 78 to a holding plate 76 secured at eachof two sites on the outside of the end portion of the funnel-likeportion 6 of the case 4. Each holding plate 76 is positioned parallel tothe surface F, and each rod end 74 is positioned so as to be erected onthat side of each holding plate 76 which does not face the surface F.Also, in the main oscillating body 66, a rod end 84 is rotatablyconnected, at each of two sites on the subordinate oscillating axis L2,by a bolt 80, which is mounted so as to protrude radially inwardly ofthe main oscillating body 66, and a nut 82. Each rod end 84 is fixed bya bolt 86 to each of both end portions of the subordinate oscillatingbody 68 comprising a plate member substantially rectangular in shape.The subordinate oscillating body 68 is positioned parallel to thesubordinate oscillating axis L2, and each rod end 84 is positioned so asto be erected on that side of the subordinate oscillating body 68 whichfaces the surface F. The intersection of the main oscillating axis L1and the subordinate oscillating axis L2 defines the axis center P1.

Another preferred embodiment of the swivel bearing mechanism 60 may be aknown spherical bearing with a shaft holding hole (not shown). Thisspherical bearing is mounted on the other opening end portion of thecase 4. In the shaft holding hole is held the oscillating tube 62 aspassing through the hole. In this swivel bearing mechanism, a sealablegap is not provided between the oscillating tube 62 and the otheropening end portion in the case 4. However, the spherical bearing itselfhas a sealing function, and so there is no problem with the formation ofthe pressure reduction space 14.

At the center of the subordinate oscillating body 68 is fixed thecylindrical oscillating tube 62 as passing through the subordinateoscillating body 68. That is, a through-hole 69 is formed at the centerof the subordinate oscillating body 68, and the oscillating tube 62 isinserted in the through-hole 69 as passing therethrough. Nearly at thecenter in the axial direction of the oscillating tube 62 is fixed aflange 63 protruding radially outwardly. This flange 63 is positioned soas to contact that side of the subordinate oscillating body 68 whichfaces the surface F. Because the flange 63 is fixed to the subordinateoscillating body 68 by a suitable fixing means such as a bolt and a nutor a weld, the oscillating tube 62 is fixed to the subordinateoscillating body 68. A part of the oscillating tube 62 and the nozzle 64are positioned so as to protrude into the case 4, i.e., the pressurereduction space 14 through the other opening end portion of the case 4.Between the other opening end portion of the case 4 and the oscillatingtube 62 there is a sealable gap which is sealed by an oscillating partsealing means 88 provided between the other opening end portion of thecase 4 and the oscillating tube 62. The oscillating part sealing means88 may be composed of a suitable material, such as synthetic rubber,which has flexibility and has the function to seal a fluid in. Assumethat a plane parallel to the object surface F and passing through theaxis center P1 of the swivel bearing mechanism 60 is a boundary surface.Then, the space that exists between this boundary surface and thesurface F and belongs to the zone where the oscillating tube 62 and thenozzle 64 move is surrounded by the case 4, the surface F, the surfacesealing means 12, and the oscillating part sealing means 88, whereby thepressure reduction space 14 is defined.

In Referring to FIGS. 2 and 10, the nozzle 64 has an ultrahigh pressurewater nozzle (orifice) 64a, a mixing chamber 64b disposed downstreamthereof for mixing ultrahigh pressure water with abrasive grains, and amixing nozzle 64c disposed downstream of the mixing chamber 64b forejecting a mixture of ultrahigh pressure water and abrasive grains. To aside surface on the other end portion side of the oscillating tube 62are connected separately an ultrahigh pressure water hose 90 and a hose92 for supply of abrasive grains (shown only in FIG. 10). Inside of theoscillating tube 62 are provided two flow paths, an ultrahigh pressurewater flow path 94 and a flow path 96 for supply of abrasive grains. Oneend of the ultrahigh pressure water flow path 94 is connected to theultrahigh pressure water hose 90, while the other end of it is connectedto the upstream side of the ultrahigh pressure water nozzle 64a of thenozzle 64. As a result, the ultrahigh pressure water hose 90 and thenozzle 64 are connected to each other via the oscillating tube 62 as ajoint. On the other hand, one end of the flow path 96 for supply ofabrasive grains is connected to the hose 92 for supply of abrasivegrains, while the other end of it is connected to the mixing chamber 64bof the nozzle 64. As a result, the hose 92 for supply of abrasive grainsand the mixing chamber 64b of the nozzle 64 are connected to each othervia the oscillating tube 62 as a joint. The other end of the flow path96 for supply of abrasive grains is connected to the mixing chamber 64bvia a connecting hose 97 provided so as to connect one end portion ofthe oscillating tube 62 to the inlet for abrasive grains of the mixingchamber 64b. The ultrahigh pressure water hose 90 is connected to anultrahigh pressure water feeding means 98, while the hose 92 for supplyof abrasive grains is connected to an abrasive grains feeding means 99.The ultrahigh pressure water feeding means 98 may be composed of, say,an ultrahigh pressure water pump, and the abrasive grains feeding means99 may be composed of, say, an abrasive grains quantitatively feedingmeans.

Next, a self-revolving/else-revolving mechanism 100, which makes theoscillating tube 62 and the nozzle 64 self-revolve and else-revolveabout the axis center P1 of the swivel bearing mechanism 60, will bedescribed with reference to FIGS. 1 to 5. Theself-revolving/else-revolving mechanism 100 has a main crank 106 havinga driven shaft 104 which is positioned on an axis L3 passing through theaxis center P1 of the swivel bearing mechanism 60 on the other endportion side of the oscillating tube 62 and which is rotationally drivenby a geared motor 102 constituting a driving means, the main crank 106being rotationally driven integrally with the driven shaft 104; asubordinate crank 110 having a rotating shaft 108 mounted at a siteeccentric from the axis L3 of the main crank 106 and having an axis L4obliquely intersecting the axis L3 of the main crank 106; a sphericaljoint 112 being a universal joint means connecting that site in thesubordinate crank 110 which is eccentric from the axis L4, to the otherend portion side of the oscillating tube 62; a subordinate bevel gear114 connected to the rotating shaft 108 of the subordinate crank 110 androtating integrally with the subordinate crank 110; and a main bevelgear 118 being provided integrally on a shaft 116 which has the axis L3common to the driven shaft 104 of the main crank 106 and which isdisposed rotatably relative to the driven shaft 104, and being engagedwith the subordinate bevel gear 114. The relation of the subordinatebevel gear 114 to the main bevel gear 118 is defined such that thesubordinate bevel gear 114 revolves about the main bevel gear 118according to the rotation of the main crank 106 while revolving on itsown axis.

The self-revolving/else-revolving mechanism 100 will be described inmore detail. At the central part in the right-and-left direction(FIG. 1) of the mounting portion 30 of the case frame 24 is fixed oneend of a foot 120 upright in a direction opposite to the surface F. Theother end of the foot 120 is coupled integrally to one end portion of aholding portion 122 extending parallel to the surface F. The other endportion of the holding portion 122 is coupled, at a site on the axis L3of the main crank 106, integrally to a central part of a holding portion124 extending in the right-and-left direction of FIG. 1 and parallel tothe surface F. One end portion of the holding portion 124 (the left endportion in FIGS. 1 and 3) is coupled integrally to the other end of afoot 126 which extends toward the surface F and whose one end is fixedto an annular flat shoulder portion 7 formed between the funnel-likeportion 6 and the torus-like portion 8 in the case 4. The other endportion of the holding portion 124 (the right end portion in FIGS. 1 and3) is coupled integrally to the other end of a foot 128 which extendstoward the surface F and whose one end is fixed to the annular flatshoulder portion 7 formed between the funnel-like portion 6 and thetorus-like portion 8 in the case 4. The holding portions 122 and 124,and the feet 120, 126 and 128 have a cross section substantially shapedlike a channel.

One end portion of the shaft 116 of the main bevel gear 118 is fixed bymeans of a nut 132 to a shaft holding portion 130 formed on the holdingportion 124 so that the shaft 116 is not rotatable. The other endportion of the shaft 116 is positioned so as to protrude from theholding portion 124 toward the surface F. To this other end portion ofthe shaft 116 is fixed the main bevel gear 118. The driven shaft 104 ofthe main crank 106 is rotatably supported on the shaft 116 of the mainbevel gear 118 via a ball bearing 134. The rotating shaft 108 of thesubordinate crank 110 is rotatably supported on the main crank 106 via aball bearing 136. One end of the spherical joint 112 is fixed to thesubordinate crank 110, and a sphere 138 is formed in the other end ofit. The sphere 138 is connected relatively rotatably to a suitablesphere receiving means provided at the other end portion side of theoscillating tube 62. To the driven shaft 104 of the main crank 106 isfixed a sprocket 140. On the foot 120 is mounted the geared motor 102.To the output shaft of the geared motor 102 is fixed a sprocket 142.Between the sprocket 140 and the sprocket 142 is mounted a roller chain144. Therefore, when the geared motor 102 is energized (actuated), themain crank 106 is rotationally driven via the sprocket 142, the rollerchain 144, the sprocket 140, and the driven shaft 104. Theoretically, astructure is feasible in which the one end of the spherical joint 112 isfixed to the other end portion side of the oscillating tube 62, and thesphere 138 is connected relatively rotatably to a suitable spherereceiving means provided in the subordinate crank 110.

The surface treating device 2 having the foregoing construction will bedescribed. With reference to FIGS. 1 to 4, when the pressure reducingmeans 22 is energized (actuated), a fluid within the pressure reductionspace 14, such as the air, is discharged to the outside through thesuction hose 20, whereupon the pressure reduction space 14 is reduced inpressure. Once the pressure reduction space 14 has been reduced inpressure, the pressure of an ambient fluid, such as the air, acting onthe case 4 owing to the difference in fluid pressure between the insideand the outside of the pressure reduction space 14 is transmitted to thesurface F via the transverse frames 34 and 38, traveling frames 42 and44, and each wheel 46. Thus, the device 2 is caused to suction-adhere tothe surface F by the pressure of the ambient fluid. In such a state ofsuction-adhesion, moreover, when each geared motor 48 is energized, thedevice 2 is moved along the surface F while suction-adhering to thesurface F.

Referring to FIGS. 2 to 5, the actions of the swivel bearing mechanism60 will be described. The main oscillating body 66 is free to pivotabout the main oscillating axis L1, while the subordinate oscillatingbody 68 is free to pivot about the subordinate oscillating axis L2.Thus, the oscillating tube 62 supported on the subordinate oscillatingbody 68 and the nozzle 64 are free to pivot about the axis center P1 ofthe swivel bearing mechanism 60. However, the oscillating tube 62 itselfdoes not revolve one axis.

The actions of the self-revolving/else-revolving mechanism 100 will bedescribed with reference to FIGS. 5 to 7. When the geared motor 102 isenergized, the main crank 106 is rotationally driven. As a result, thesubordinate bevel gear 114 revolves about the main bevel gear 118, butthe main bevel gear 118 is fixed so as not to rotate. Hence, inaccordance with the rotation of the main crank 106, the subordinatebevel gear 114 and the subordinate crank 110 integral with thesubordinate bevel gear 114 revolve on their own axes. The revolution ofthe subordinate crank 110 on its own axis, and the revolution of themain crank 106 about some member else are transmitted to the other endportion side of the oscillating tube 62 via the spherical joint 112provided at a portion eccentric from the axis L4 of the subordinatecrank 110. As aforementioned, on the other hand, the oscillating tube 62is free to pivot about the axis center P1 of the swivel bearingmechanism 60; thus, the oscillating tube 62 and the nozzle 64self-revolve and else-revolve about the axis center P1 of the swivelbearing mechanism 60 as the center of revolution.

In FIGS. 5 to 7, the angle at which the axis L4 of the subordinate bevelgear 114 obliquely intersects the axis L3 of the main bevel gear 118 isexpressed as Q; the point of the oblique intersection, as P2; thedistance between the axis L4 of the subordinate crank 110 and the axisL5 of the spherical joint 112, as a; and the distance between thesurface of revolution of the center P3 of the sphere 138 of thespherical joint 112 and the axis center P1 of the swivel bearingmechanism 60, as b.

When referring to FIGS. 4 and 10, by actuating the ultrahigh pressurewater feeding means 98 and the abrasive grains feeding means 99,ultrahigh pressure water and abrasive grains are ejected vigorouslytoward the object surface F from the nozzle 64 revolving on its own axisand about some member else. After the ultrahigh pressure water andabrasive grains collided with the surface F, they are sucked andrecovered by the pressure reducing means 22 through the suction hose 20together with foreign matter peeled off the surface F.

Next, a self-revolving/else-revolving mechanism 200 provided partly withthe other embodiment will be described with reference to FIGS. 8 and 9.In these drawings, the same parts as in FIGS. 1 to 7 are shown by thesame numerals. In the structure explained in FIGS. 1 to 7, the mainbevel gear 118 is fixed to the shaft holding portion 130 of the holdingportion 124. In the self-revolving/else-revolving mechanism 200 in FIGS.8 and 9, the main bevel gear 118 rotates. That is, the shaft 202 of themain bevel gear 118 is rotatably mounted in a shaft holding portion 204of a holding portion 124 via a ball bearing 206. The shaft 202 isfurther fixed in a hollow shaft (not shown) of a hollow-shaft typegeared motor 210 secured to a flange 208 provided on the shaft holdingportion 204. In the above construction, when the geared motor 210 isenergized to rotate the main bevel gear 118 in a direction opposite tothe revolution of the main crank 106 about some member else, the speedof revolution of the subordinate crank 110 and the subordinate bevelgear 114 on their own axes can be made even higher. If the geared motor210 is adapted not to be rotatable, by using a suitable braking means,the main bevel gear 118 can be held in a fixed condition.

While the present invention has been described in detail hereinabove onthe basis of some embodiments, it should be understood that theinvention is not limited to these embodiments, but various changes andmodifications are possible without departing from the scope of theinvention. For example, in the embodiments of the present invention, themechanism for transmitting revolution between the obliquely intersectingaxes in the self-revolving/else-revolving mechanism 100 is composed ofthe main bevel gear 118 and the subordinate bevel gear 114; however, theinvention is not limited to this construction. Concretely, the mechanismfor transmitting revolution between the obliquely intersecting axes maybe constituted from a main roller and a subordinate roller each of asimilar shape, instead of the main bevel gear 118 and the subordinatebevel gear 114. The main roller and the subordinate roller each have aconical circumferential portion formed thereon. Friction upon contactthat occurs when their conical surfaces are pressed against each otherresults in the transmission of revolutions. This construction is alsoincluded within the scope of the present invention. The explanations forthe embodiments of the instantly invented device have hereinbefore beenmade on the assumption that the device 2 is present on a surface in theair. However, the device of the invention is applicable in water aswell. In this case, a water pump or a water ejector may be used insteadof a vacuum pump as the pressure reducing means 22.

I claim:
 1. A surface treating device having a nozzle for ejecting a surface treating material toward the surface of an object, which comprisesa swivel bearing mechanism, an oscillating tube connected to the swivel bearing mechanism so as to be free to pivot about an axis center of the swivel bearing mechanism and such that with respect to the axis center, an end portion thereof is positioned on the side facing the object surface and the other end portion thereof is positioned on the side opposite to the object surface, the nozzle connected to the one end portion side of the oscillating tube, and a self-revolving/else-revolving mechanism connected to the other end portion side of the oscillating tube and making the nozzle self-revolve and else-revolve about the axis center of the swivel bearing mechanism, the self-revolving/else-revolving mechanism including a main crank which has a driven shaft positioned on an axis passing through the axis center of the swivel bearing mechanism on the other end portion side of the oscillating tube and rotationally driven by driving means, and which is rotationally driven integrally with the driven shaft; a subordinate crank having a rotating shaft mounted at a site eccentric from the axis of the main crank and having an axis obliquely intersecting the axis of the main crank; universal joint means connecting that site in the subordinate crank which is eccentric from the axis, to the other end portion side of the oscillating tube; a subordinate bevel gear connected to the rotating shaft of the subordinate crank and rotating integrally with the subordinate crank; a main bevel gear which is provided integrally on a shaft having an axis common to the driven shaft of the main crank and being disposed so as to be free to rotate relative to the driven shaft, and which is engaged with the subordinate bevel gear; and the subordinate bevel gear revolving about the main bevel gear according to the rotation of the main crank while revolving on its own axis.
 2. The surface treating device of claim 1 wherein the shaft of the main bevel gear is fixed so as not to rotate.
 3. The surface treating device of claim 1 wherein the shaft of the main bevel gear is drivingly connected to other driving means so that the main bevel gear may be rotationally driven in a direction opposite to the direction of rotation of the main crank.
 4. The surface treating device of any one of claims 1 to 3 wherein the swivel bearing mechanism includes an annular main oscillating body having a main oscillating axis on a plane parallel to the surface of the object, and a plate-like subordinate oscillating body connected to the main oscillating body so as to have a subordinate oscillating axis perpendicularly intersecting the main oscillating axis of the main oscillating body, with the oscillating tube being connected to the subordinate oscillating body.
 5. The surface treating device of any one of claims 1 to 3 wherein a space, which has as a boundary a plane parallel to the surface of the object and passing the axis center of the swivel bearing mechanism, which is present between the boundary surface and the surface of the object, and which belongs to a zone where the oscillating tube and the nozzle move, is surrounded by a tubular case opening at both end portions, by the surface, by surface sealing means mounted at that one opening end portion of the case which faces the surface to seal a gap between the case and the surface, and by oscillating part sealing means for sealing a gap present between the other opening end portion in the case facing the boundary surface and the oscillating tube, whereby a pressure reduction space is defined, the pressure reduction space being connected to pressure reducing means for discharging a fluid from the pressure reduction space to decrease the pressure inside the pressure reduction space.
 6. The surface treating device of claim 5 wherein the case is equipped with moving means, the device is caused to suction-adhere to the surface by the pressure of an ambient fluid acting on the case owing to the difference in fluid pressure between the inside and the outside of the case upon the actuation of the pressure reducing means, and the device is movable along the surface by the action of the moving means. 